Process of manufacturing a sea-water-resisting cement from blast-furnace slag.



UNITED. STATES PATENT oEEIoE.

HEINRICH COLLOSEUS, OF BERLIN, GERMANY, ASSIGNOR, BY MESNE ASSIGNMENTS,TO COLLOSEUS CEMENT COMPANY, A CORPORATION OF NEW JERSEY.

PROCESS OF'MANUFACTURING A SEA-WATER-RESISTING CEMENT FROM BLAST-FURNACE SLAG.

Specification of Letters Patent.

Patented July 21, 1908.

Application filed May 17, 1907. Serial No. 374,244.

To all whom it may concern:

Be it known that I, HEINRICH CoLLosEUs, a chemist and a doctor ofphiloso hy, a subject of the German Emperor, an a resident of 15Spichernstrasse, in the city of Berlin, Kingdom of Prussia, and GermanEmpire, have invented a certain new and useful Process of Manufacturinga Sea-Water-Resisting Cement from Blast-Furnace Slag, of which thefollowing is a specification.

This invention has reference to a rocess for manufacturing cement fromblast urnace slag by the introduction of certain, hereinafter specifiedsalt solutions into the freshly prepared blast furnace slag, as drawnfrom the furnace, the said cement being ready to be used directlywithout any further additions. As compared withthe previous procass ofconverting blast furnace slag into finished cement by the introductionof small amounts of solutions of water soluble alkali salts or of thesalts of alkaline earths or of the earth metals, whereby a cement whichforms a perfect substitute for ordinary Portland cement is obtained, thepresent process hereinafter described, is distinguished by the fact,that the cement obtained by the treatment with salt solutions possessesparticularly resisting qualities against the action of seawater. Thisobject is attained in my process by the utilization of the well-knownresearches of Le Chatelier, Newberry and Michaelis, who have shown thatit is possible to obtain a cement which will resist the action ofsea-water by replacing the alumina of the ordinary Portland cement byoxid of iron, my process being carried out by incorporating with the hotliquid slag, as freshly tapped from the furnace, small quantities ofiron or of manganese, chromium, nickel and the like as aqueous solutionsof any water soluble salts of the iron group, that is to say anysuitable salt of iron, manganese, chromium or the like. By the injectionof small amounts of salt solutions into the hot liquid blast furnaceslag a physical or molecular change is known to take place in the slagpartly. by the sudden vaporization of the in-.

jected water, which is finely distributed throughout the slag and partlyby the dissociation of the salt itself, the free lime, or a veryessential proportion of the same being neutralized at the same timemostly by the effects of the dissociation, but furthermore than that, inView of the fact, that iron, m anganese or chromium are incorporatedwith the slag in the nascent state, so to speak, immediately upon theirliberation from the salts and to some extent most robably in the form offreshly liberated, co oidal oxid, which is therefore especially capableof immediate reaction, the property of being able to resist thedestructive influences of the sulfuric acid compounds of the sea-wateris imparted to the product, the iron, manganese and the like probablycombining with the silicates and the lime, to form the bodies, whichhave been exhaustively studied by Newberry and Le Chatelier in their researches. Of course, mixtures of different metals of the iron group mayalso be used.

The perfectly dry product, obtained in accordance with this invention bythe injection of solutions into the freshly drawn hot liquid slag, afterhaving been cooled and ground to a fine flour, yields a finished cement,which is equivalent to Portland cement and which resists the action ofsea water. The process is for instance carried out by allowing the hotliquid slag to flow in the well known manner upon the outer surface of arapidly rotating drum, which by its rapid rotation produces a thoroughdisintegration of the particles flowing onto it. Simultaneously with theflowing of the sla onto the outer surface of the drum, the requiredamount of the solutions, thus for instance, a solution of sulfate ofiron, is also caused to flow by means of any suitable device onto thedrum. If required, the introduction of the salt solutions may beeffected by means of a sprayer.

In the case of slags with from 46 to 52 per cent. of lime and 28 to 32per cent. of silicic acid, and 12 to 16 percent. of alumina, 10 to 30grams of a 5 per cent. solution of the salt for 100 grams of slag areinjected.

What I claim and desire to secure by Let ters Patent of the UnitedStates is 1. The process of manufacturing seawater resisting cement bycombining therewith while in the form of spray of molten particles, asalt of the iron group which is immediately decomposed under the actionof the heat while its water of solution is evaporated and assists todisintegrate and partly cool the slag, substantially as described.

2. The process of incor crating salts of the iron group with molten s agfor the purpose of forming sea water resisting cement, which consists inbringing both the slag and the solution of salt into. the form of aspray and allowing them to act on each other while in this form,substantially as described.

3. The process of manufacturing a sea water resisting cement, whichconsists in bringing molten slag into a spray-like condition andincorporating therewith from 7% to 1% per cent. of salts of the ironstantially as described.

In witness whereof I have hereunto signed my name this 2nd day of Ma;1907, in the presence of two subscribing witnesses.

- HEINRICH COLLOSEUS.

Witnesses:

WOLDEMAR HAUPT, HENRY HASPER.

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